1. Technical Field
The present invention relates to an apparatus and method for extending a sound signal from a mono sound signal into a stereo sound signal.
2. Description of the Related Art
It has been widely known that a stereo sound signal can provide greater user satisfaction than a mono signal.
A stereo signal contains more data than a mono signal and requires more complicated electronic devices than a mono signal. Thus, a mono signal is often used due to communication environments and requirements of the electronic device. Nevertheless, users prefer stereo signals and there is need for a method of obtaining a stereo signal when a mono signal is received or stored.
As a conventional method for listening to a mono signal in the form of a stereo signal, there has been proposed “Artificial stereo extension of speech based on inter-channel coherence” Advanced Science and Technology Letters (ASTL), Vol. 14, pp.168-171(2012). The proposed method employs interchannel coherence (ICC) to obtain a stereo signal from a mono signal.
However, the conventional method has a problem in that an obtained stereo signal is different from a real signal due to variation of ICC of the real signal. Therefore, it is difficult to satisfy listeners.